Log in

Connect faster with

Register

Signup faster with


|   Education without borders.
Menu
a Guest

Trignometric identities

Prove that, 2sina(cos2a+cos4a+cos6a)=sin7a-sina

Posted in Trigonometry, asked by Daniel joe, 6 years ago. 2254 hits.

-1

given equation is,2sina(cos2a+cos4a+cos6a)=sin7a-sina

so we will take the sina to L.H.S

sina(2cos2a+2cos4a+2cos6a)+sina=sin7a

sina(2cos2a+2cos4a+2cos6a+1)=sin7a

according to the formula,2cos2a+2cos4a+2cos6a+1=sin7a/sina

so we substitute the  given equation in the formula,

sina(sin7a/sina)=sin7a

so,we cancel the sina at L.H.S

sin7a=sin7a

L.H.S=R.H.S

Venkat Nagendra Thati
Venkat Nagendra Thati - 6 years ago
Ask Venkat Nagendra Thati for further help.
Report
Please register/login to answer this question. 
- Just now

0

a Guest
Just now
× Attachments/references, if any, will be shown after refreshing the page.
/homework-help
/homework-help/get_answer/228
/homework-help/save_reply/228
/homework-help/save_answer/228
/homework-help/accept_answer/228
/homework-help/unaccept_answer/228
/homework-help/unpublish_answer/228
/homework-help/delete_answer/228
/homework-help/update_answer/228
/homework-help/like/228
/homework-help/dislike/228
/homework-help/report_answer/228
/homework-help/report_question/228
/homework-help/save_bounty/228